X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imo-d22.mx.aol.com ([205.188.144.208] verified) by logan.com (CommuniGate Pro SMTP 4.3.5) with ESMTP id 1026858 for flyrotary@lancaironline.net; Thu, 30 Jun 2005 03:00:37 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.144.208; envelope-from=Lehanover@aol.com Received: from Lehanover@aol.com by imo-d22.mx.aol.com (mail_out_v38_r1.7.) id q.205.4a26c2d (57317) for ; Thu, 30 Jun 2005 02:59:45 -0400 (EDT) From: Lehanover@aol.com Message-ID: <205.4a26c2d.2ff4f261@aol.com> Date: Thu, 30 Jun 2005 02:59:45 EDT Subject: Re: [FlyRotary] Re: P Ports working on dyno To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1120114784" X-Mailer: 9.0 SE for Windows sub 5012 -------------------------------1120114784 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 6/29/2005 8:18:35 PM Pacific Daylight Time, lendich@optusnet.com.au writes: There are only two runners instead of four so naturally the speed will have to be double assuming the same size runners. If in the case of side port, the intake runner i.d.s are reduced, the skin friction will be greatly increased. Face it, side ports are a drag. There is no way velocities in a four runner intake can ever approach those of a two runner p port. IMHO, Jerry In order to deliver the same CFM at the same depression, the single runner need not equal the cross section of two runners. To say it another way: A single runner of the same cross section as the two it replaces, will deliver the same CFM at a lower velocity. The larger the tube, the lower the velocity. Lower velocity = lower drag. Drag increases at about the cube of velocity. So the single tube is far more efficient than the two tubes with half the cross section. Plus no losses caused by the turns. Lynn E. Hanover -------------------------------1120114784 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
In a message dated 6/29/2005 8:18:35 PM Pacific Daylight Time,=20 lendich@optusnet.com.au writes:
<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>There=20 are only two runners instead of four so naturally the speed will have to b= e=20 double assuming the same size runners. If in the case of side port, the in= take=20 runner i.d.s are reduced, the skin friction will be greatly increased. Fac= e=20 it, side ports are a drag. There is no way velocities in a four runner int= ake=20 can ever approach those of a two runner p port. IMHO,=20 Jerry
In order to deliver the same CFM at the same depression, the single run= ner=20 need not equal the cross section of two runners. To say it another way: A si= ngle=20 runner of the same cross section as the two it replaces, will deliver the sa= me=20 CFM at a lower velocity. The larger the tube, the lower the velocity. Lower=20 velocity =3D lower drag.
 
Drag increases at about the cube of velocity. So the single tube is far= =20 more efficient than the two tubes with half the cross section. Plus no=20 losses caused by the turns.
 
Lynn E. Hanover
-------------------------------1120114784--